Lens hood are primarily designed to stop light coming into the lens at extreme angles and being reflected inside the lens. This can lower the contrast of the image. Lens hoods also have two other very practical uses. Since the end of the lens is extended, you also get the added benefit of some extra protection from accidental impact, and also help to keep your fingers away from the front of the lens
 
 
Compatible with
 
CANON EF 50mm f/1.4 USM
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